ARTS 2.5.0 (git: 9ee3ac6c)
matpackI.h File Reference

Implementation of Matrix, Vector, and such stuff. More...

#include <Eigen/Dense>
#include "array.h"
#include "matpack.h"

Go to the source code of this file.

## Classes

class  Joker
The Joker class. More...

class  Range
The range class. More...

class  Iterator1D
The iterator class for sub vectors. More...

class  ConstIterator1D
The constant iterator class for sub vectors. More...

class  ConstVectorView
A constant view of a Vector. More...

class  VectorView
The VectorView class. More...

class  Iterator2D
The row iterator class for sub matrices. More...

class  ConstIterator2D
The const row iterator class for sub matrices. More...

class  Vector
The Vector class. More...

class  ConstMatrixView
A constant view of a Matrix. More...

class  MatrixView
The MatrixView class. More...

class  Matrix
The Matrix class. More...

## Typedefs

typedef Eigen::Stride< Eigen::Dynamic, Eigen::Dynamic > StrideType

typedef Eigen::Matrix< Numeric, Eigen::Dynamic, Eigen::Dynamic, Eigen::RowMajor > MatrixType

typedef Eigen::Map< MatrixType, 0, StrideTypeMatrixViewMap

typedef Eigen::Map< const MatrixType, 0, StrideTypeConstMatrixViewMap

typedef Eigen::Matrix< Numeric, 4, 4, Eigen::RowMajor > Matrix4x4Type

typedef Eigen::Map< Matrix4x4Type, 0, StrideTypeMatrix4x4ViewMap

typedef Eigen::Map< const Matrix4x4Type, 0, StrideTypeConstMatrix4x4ViewMap

## Functions

void copy (ConstIterator1D origin, const ConstIterator1D &end, Iterator1D target)

void copy (Numeric x, Iterator1D target, const Iterator1D &end) ARTS_NOEXCEPT
Copy a scalar to all elements. More...

void copy (ConstIterator2D origin, const ConstIterator2D &end, Iterator2D target)
Copy data between begin and end to target. More...

void copy (Numeric x, Iterator2D target, const Iterator2D &end) ARTS_NOEXCEPT
Copy a scalar to all elements. More...

void mult (VectorView y, const ConstMatrixView &M, const ConstVectorView &x)
Matrix-Vector Multiplication. More...

void mult_general (MatrixView A, const ConstMatrixView &B, const ConstMatrixView &C) ARTS_NOEXCEPT
General matrix multiplication. More...

void mult (MatrixView A, const ConstMatrixView &B, const ConstMatrixView &C)
Matrix-Matrix Multiplication. More...

void cross3 (VectorView c, const ConstVectorView &a, const ConstVectorView &b) ARTS_NOEXCEPT
cross3 More...

Numeric vector_angle (ConstVectorView a, ConstVectorView b)

void proj (Vector &c, ConstVectorView a, ConstVectorView b) ARTS_NOEXCEPT

ConstMatrixView transpose (ConstMatrixView m) ARTS_NOEXCEPT
Const version of transpose. More...

MatrixView transpose (MatrixView m) ARTS_NOEXCEPT
Returns the transpose. More...

void transform (VectorView y, double(&my_func)(double), ConstVectorView x)
A generic transform function for vectors, which can be used to implement mathematical functions operating on all elements. More...

void transform (MatrixView y, double(&my_func)(double), ConstMatrixView x)
A generic transform function for matrices, which can be used to implement mathematical functions operating on all elements. More...

Numeric max (const ConstVectorView &x) ARTS_NOEXCEPT
Max function, vector version. More...

Numeric max (const ConstMatrixView &x) ARTS_NOEXCEPT
Max function, matrix version. More...

Numeric min (const ConstVectorView &x) ARTS_NOEXCEPT
Min function, vector version. More...

Numeric min (const ConstMatrixView &x) ARTS_NOEXCEPT
Min function, matrix version. More...

Numeric mean (const ConstVectorView &x) ARTS_NOEXCEPT
Mean function, vector version. More...

Numeric nanmean (const ConstVectorView &x) ARTS_NOEXCEPT
Mean function, vector version ignoring nans and infs. More...

Numeric mean (const ConstMatrixView &x) ARTS_NOEXCEPT
Mean function, matrix version. More...

Numeric operator* (const ConstVectorView &a, const ConstVectorView &b) ARTS_NOEXCEPT
Scalar product. More...

std::ostream & operator<< (std::ostream &os, const ConstVectorView &v)

std::ostream & operator<< (std::ostream &os, const ConstMatrixView &v)
Output operator. More...

std::ostream & operator<< (std::ostream &os, const Range &r)

ConstMatrixViewMap MapToEigen (const ConstMatrixView &A)

ConstMatrix4x4ViewMap MapToEigen4x4 (const ConstMatrixView &A)

ConstMatrixViewMap MapToEigen (const ConstVectorView &A)

ConstMatrixViewMap MapToEigenRow (const ConstVectorView &A)

ConstMatrixViewMap MapToEigenCol (const ConstVectorView &A)

MatrixViewMap MapToEigen (MatrixView &A)

Matrix4x4ViewMap MapToEigen4x4 (MatrixView &A)

MatrixViewMap MapToEigen (VectorView &A)

MatrixViewMap MapToEigenRow (VectorView &A)

MatrixViewMap MapToEigenCol (VectorView &A)

Numeric debug_matrixview_get_elem (MatrixView &mv, Index r, Index c)
Helper function to access matrix elements. More...

## Variables

const Joker joker

## Detailed Description

Implementation of Matrix, Vector, and such stuff.

Date
2001-06-12

A VectorView consists of the data, which is stored in a continuous piece of memory, and a selection, specified by start, extend, and stride. A Vector is a VectorView which also allocates its memory automatically.

VectorViews can not be generated directly, they only result from operations on Vectors, such as using the index operator with a Range object. However, you can store them, like:

VectorView A = B[Range(0,3)]

A VectorView acts like a reference to the selected region in the parent matrix. Functions that operate on an existing matrix (i.e., they do not use resize) should take VectorView x as arguement, rather than Vector& x. That has the advantage that they can be called either with a VectorView or Vector. E.g., if you have:

then you can call the function in these two ways:

fill_with_junk(v); fill_with_junk(v[Range(1,3)])

Assignment (=) copies the data from one Vector or VectorView to another one. Dimensions must agree. Only exceptions are the copy constructors which automatically set the dimensions to match.

Things work in the same way for the type Matrix.

There exist operators *=, /=, +=, and -= to multiply (divide,...) by a scalar. Plain operators *,... do not exist, because they would result in the creation of temporaries and therefor be inefficient.

However, you can use * to compute the scalar product. This is efficient, since the return value is just a scalar.

There is a constructor for vector filling it with a sequence of values.

Matrices:

You can extract sub matrices (MatrixView) using Range objects. You can also extract rows and columns this way.

transpose(A) Returns a special MatrixView that is the transpose of the original. The original is not changed by this!

mult(A,B,C) computes A = B*C Note that the order is different from MTL (output first)!

A VectorView or Vector can be taken in the place of a nx1 matrix. That means, Vectors are interpreted as column vectors. Hence, you can compute:

mult(a,M,b); // a = M*b

but also, by using transpose:

mult(transpose(b),transpose(a),M); // b^t = a^t * M

See the section about Matrices and Vectors in the ARTS user guide for more details.

Definition in file matpackI.h.

## ◆ ConstMatrix4x4ViewMap

 typedef Eigen::Map ConstMatrix4x4ViewMap

Definition at line 119 of file matpackI.h.

## ◆ ConstMatrixViewMap

 typedef Eigen::Map ConstMatrixViewMap

Definition at line 116 of file matpackI.h.

## ◆ Matrix4x4Type

 typedef Eigen::Matrix Matrix4x4Type

Definition at line 117 of file matpackI.h.

## ◆ Matrix4x4ViewMap

 typedef Eigen::Map Matrix4x4ViewMap

Definition at line 118 of file matpackI.h.

## ◆ MatrixType

 typedef Eigen::Matrix MatrixType

Definition at line 114 of file matpackI.h.

## ◆ MatrixViewMap

 typedef Eigen::Map MatrixViewMap

Definition at line 115 of file matpackI.h.

## ◆ StrideType

 typedef Eigen::Stride StrideType

Definition at line 112 of file matpackI.h.

## ◆ copy() [1/4]

 void copy ( ConstIterator1D origin, const ConstIterator1D & end, Iterator1D target )

Target must be a valid area of memory. Note that the strides in the iterators can be different, so that we can for example copy data between different kinds of subvectors.

Definition at line 412 of file matpackI.cc.

## ◆ copy() [2/4]

 void copy ( ConstIterator2D origin, const ConstIterator2D & end, Iterator2D target )

Copy data between begin and end to target.

Target must be a valid area of memory. Note that the strides in the iterators can be different, so that we can for example copy data between different kinds of subvectors.

Origin, end, and target are 2D iterators, marking rows in a matrix. For each row the 1D iterator is obtained and used to copy the elements.

Definition at line 919 of file matpackI.cc.

References ConstVectorView::begin(), and Zeeman::end().

## ◆ copy() [3/4]

 void copy ( Numeric x, Iterator1D target, const Iterator1D & end )

Copy a scalar to all elements.

Definition at line 310 of file matpackI.cc.

References Zeeman::end().

## ◆ copy() [4/4]

 void copy ( Numeric x, Iterator2D target, const Iterator2D & end )

Copy a scalar to all elements.

Definition at line 931 of file matpackI.cc.

References Zeeman::end().

## ◆ cross3()

 void cross3 ( VectorView c, const ConstVectorView & a, const ConstVectorView & b )

cross3

Calculates the cross product between two vectors of length 3.

c = a x b, for 3D vectors. The vector c must have length 3 and can not be the same variable as a or b.

param c Out: The cross product vector

Parameters
 a In: A vector of length 3. b In: A vector of length 3.
Date
2012-02-12

Definition at line 1393 of file matpackI.cc.

References a, ARTS_ASSERT, b, and c.

Referenced by MCAntenna::draw_los(), and specular_losCalc().

## ◆ debug_matrixview_get_elem()

 Numeric debug_matrixview_get_elem ( MatrixView & mv, Index r, Index c )

Helper function to access matrix elements.

Because of function inlining the operator() is not accessible from the debuggger. This function helps to access Matrix elements from within the debugger.

Parameters
 mv MatrixView r Row index c Column index
Date
2004-05-10

Definition at line 1762 of file matpackI.cc.

References c.

## ◆ MapToEigen() [1/4]

 ConstMatrixViewMap MapToEigen ( const ConstMatrixView & A )

Definition at line 1090 of file matpackI.cc.

Referenced by MapToEigenRow().

## ◆ MapToEigen() [2/4]

 ConstMatrixViewMap MapToEigen ( const ConstVectorView & A )

Definition at line 578 of file matpackI.cc.

## ◆ MapToEigen() [3/4]

 MatrixViewMap MapToEigen ( MatrixView & A )

Definition at line 1091 of file matpackI.cc.

## ◆ MapToEigen() [4/4]

 MatrixViewMap MapToEigen ( VectorView & A )

Definition at line 580 of file matpackI.cc.

## ◆ MapToEigen4x4() [1/2]

 ConstMatrix4x4ViewMap MapToEigen4x4 ( const ConstMatrixView & A )

Definition at line 1093 of file matpackI.cc.

## ◆ MapToEigen4x4() [2/2]

 Matrix4x4ViewMap MapToEigen4x4 ( MatrixView & A )

Definition at line 1094 of file matpackI.cc.

## ◆ MapToEigenCol() [1/2]

 ConstMatrixViewMap MapToEigenCol ( const ConstVectorView & A )

Definition at line 579 of file matpackI.cc.

## ◆ MapToEigenCol() [2/2]

 MatrixViewMap MapToEigenCol ( VectorView & A )

Definition at line 581 of file matpackI.cc.

## ◆ MapToEigenRow() [1/2]

 ConstMatrixViewMap MapToEigenRow ( const ConstVectorView & A )

Definition at line 1685 of file matpackI.cc.

References MapToEigen().

## ◆ MapToEigenRow() [2/2]

 MatrixViewMap MapToEigenRow ( VectorView & A )

Definition at line 1716 of file matpackI.cc.

References MapToEigen().

## ◆ max() [1/2]

 Numeric max ( const ConstMatrixView & x )

Max function, matrix version.

Definition at line 1532 of file matpackI.cc.

References ConstVectorView::begin(), ConstVectorView::end(), and max().

## ◆ max() [2/2]

 Numeric max ( const ConstVectorView & x )

Max function, vector version.

Definition at line 1517 of file matpackI.cc.

References max().

Referenced by max().

## ◆ mean() [1/2]

 Numeric mean ( const ConstMatrixView & x )

Mean function, matrix version.

Definition at line 1621 of file matpackI.cc.

References ConstVectorView::begin(), ConstVectorView::end(), and mean().

## ◆ mean() [2/2]

 Numeric mean ( const ConstVectorView & x )

Mean function, vector version.

Definition at line 1585 of file matpackI.cc.

References mean().

Referenced by mean().

## ◆ min() [1/2]

 Numeric min ( const ConstMatrixView & x )

Min function, matrix version.

Definition at line 1566 of file matpackI.cc.

References ConstVectorView::begin(), ConstVectorView::end(), and min().

## ◆ min() [2/2]

 Numeric min ( const ConstVectorView & x )

Min function, vector version.

Definition at line 1551 of file matpackI.cc.

References min().

Referenced by ConstMatrixView::diagonal(), and min().

## ◆ mult() [1/2]

 void mult ( MatrixView A, const ConstMatrixView & B, const ConstMatrixView & C )

Matrix-Matrix Multiplication.

Performs the matrix multiplication A = B * C. The dimensions must match, i.e. A must be a m times n matrix, B a m times k matrix and C a k times c matrix. No memory reallocation takes place, only the data is copied. Using this function on overlapping MatrixViews belonging to the same Matrix will lead to unpredictable results. In particular, this means that A and B must not be the same matrix!

If the memory layout allows it, the multiplication is performed using BLAS' _dgemm, which leads to a significant speed up of the operation. To be compatible with BLAS the matrix views A, B and C must satisfy:

• A must have column or row stride 1
• B must have column or row stride 1
• C must have column stride 1

That means that A and B can be ConstMatrixView objects corresponding to transposed/non-transposed submatrices of a matrix, that are continuous along their first/second dimension. C must correspond to a non-transposed submatrix of a matrix, that is continuous along its second dimension.

Parameters
 [in,out] A The matrix A, that will hold the result of the multiplication. [in] B The matrix B [in] C The matrix C

Definition at line 1073 of file matpackI.cc.

## ◆ mult() [2/2]

 void mult ( VectorView y, const ConstMatrixView & M, const ConstVectorView & x )

Matrix-Vector Multiplication.

Computes the Matrix-Vector product y = M * x, for a m times n matrix M, a length-m vector y and a length-n vector x.

The product is computed using the dgemv_ routine from the BLAS library if the matrix is contiguous in memory. If this is not the case, the mult_general method is used to compute the product.

No memory is allocated for the computation and the matrix and vector views may not overlap.

Parameters
 [out] y The length-m VectorView where the result is stored. [in] M Reference to the m-times-n ConstMatrixView holding the matrix M. [in] x Reference to the length-n ConstVectorView holding the vector x.

Definition at line 566 of file matpackI.cc.

## ◆ mult_general()

 void mult_general ( MatrixView A, const ConstMatrixView & B, const ConstMatrixView & C )

General matrix multiplication.

This is the fallback matrix multiplication which works for all ConstMatrixView objects.

Parameters
 [in,out] A The matrix A, that will hold the result of the multiplication. [in] B The matrix B [in] C The matrix C

Definition at line 1079 of file matpackI.cc.

## ◆ nanmean()

 Numeric nanmean ( const ConstVectorView & x )

Mean function, vector version ignoring nans and infs.

Definition at line 1600 of file matpackI.cc.

References nanmean().

Referenced by Raw::Reduce::nanfocus(), and nanmean().

## ◆ operator*()

 Numeric operator* ( const ConstVectorView & a, const ConstVectorView & b )

Scalar product.

The two vectors may be identical.

Definition at line 539 of file matpackI.cc.

References v.

## ◆ operator<<() [1/3]

 std::ostream & operator<< ( std::ostream & os, const ConstMatrixView & v )

Output operator.

This demonstrates how iterators can be used to traverse the matrix. The iterators know which part of the matrix is ‘active’, and also the strides in both directions. This function is a bit more complicated than necessary to illustrate the concept, because the formating should look nice. This means that the first row, and the first element in each row, have to be treated individually.

Definition at line 539 of file matpackI.cc.

## ◆ operator<<() [2/3]

 std::ostream & operator<< ( std::ostream & os, const ConstVectorView & v )

Definition at line 106 of file matpackI.cc.

## ◆ operator<<() [3/3]

 std::ostream & operator<< ( std::ostream & os, const Range & r )

Definition at line 37 of file matpackI.cc.

References Range::get_extent(), Range::get_start(), and Range::get_stride().

## ◆ proj()

 void proj ( Vector & c, ConstVectorView a, ConstVectorView b )

Calculates the projection of two vectors of equal length.

c = proj_a(b). Projecting b on a. The vector c must have the same length but can not be the same variable as a or b.

Parameters
 c Out: The projection of b on a. a In: A vector of length N. b In: A vector of length N.
Date
2012-07-10

Definition at line 1434 of file matpackI.cc.

References a, ARTS_ASSERT, b, and c.

## ◆ transform() [1/2]

 void transform ( MatrixView y, double(&)(double) my_func, ConstMatrixView x )

A generic transform function for matrices, which can be used to implement mathematical functions operating on all elements.

Because we have this, we don't need explicit functions like sqrt for matrices! The type of the mathematical function is double (&my_func)(double). Numeric would not work here, since mathematical functions for float do not exist!

transform(y,sin,x) computes y = sin(x)

This function can also be used for Vectors, because there is a conversion to MatrixView.

The two Matrix views may be the same one, in which case the conversion happens in place.

Parameters
 y Output: The results of the function acting on each element of x. my_func A function (e.g., sqrt). x A matrix.

Definition at line 1500 of file matpackI.cc.

## ◆ transform() [2/2]

 void transform ( VectorView y, double(&)(double) my_func, ConstVectorView x )

A generic transform function for vectors, which can be used to implement mathematical functions operating on all elements.

Because we have this, we don't need explicit functions like sqrt for matrices! The type of the mathematical function is double (&my_func)(double). Numeric would not work here, since mathematical functions for float do not exist!

transform(y,sin,x) computes y = sin(x)

Although the matrix version of this can also be used for vectors, thanks to the automatic interpretation of a vector as a one column matrix, this one is slightly more efficient. However, the difference is very small (only a few percent).

The two views may be the same one, in which case the conversion happens in place.

Parameters
 y Output: The results of the function acting on each element of x. my_func A function (e.g., sqrt). x A vector.

Definition at line 1472 of file matpackI.cc.

## ◆ transpose() [1/2]

 ConstMatrixView transpose ( ConstMatrixView m )

Const version of transpose.

Definition at line 1070 of file matpackI.cc.

## ◆ transpose() [2/2]

 MatrixView transpose ( MatrixView m )

Returns the transpose.

This creates a special MatrixView for the transpose. The original is not changed!

Definition at line 1203 of file matpackI.cc.

References M.

## ◆ vector_angle()

 Numeric vector_angle ( ConstVectorView a, ConstVectorView b )

Returns numeric angle between two vectors in degrees.

Parameters
 a In: A vector of length N. b In: A vector of length N.
Date
2012-07-10

Definition at line 1412 of file matpackI.cc.

References a, ARTS_ASSERT, b, and sqrt().

## ◆ joker

 const Joker joker
extern

Referenced by Range::operator()().